The invention relates to a water filtration system having a locking and unlocking mechanism for changing the filter when the filter media has served its useful life. The use of liquid filtration devices is well known in the art as shown in U.S. Pat. Nos. 5,135,645, 5,914,037 and 6,632,355. Although these patents show filters for water filtration, the filters are difficult to replace owing to their design and placement. For example, U.S. Pat. No. 5,135,645 discloses a filter cartridge as a plug-in cartridge with a series of switches to prevent the flow of water when the filter cartridge is removed for replacement. The filter must be manually inserted and removed and have a switch activated to activate valve mechanisms so as to prevent the flow of water when the filter is removed. The cover of the filter is placed in the sidewall of a refrigerator and is employed to activate the switches that activate the valves. The filter access is coplanar with the refrigerator wall and forces an awkward access to the filter cartridge.
In U.S. patent application Ser. No. 11/511,599 filed on Aug. 28, 2006, for Huda, entitled “FILTER HOUSING APPARATUS WITH ROTATING FILTER REPLACEMENT MECHANISM,” a filter assembly having a rotator actuating mechanism including a first internal rotator and a second internal rotator is taught as an efficient way to insert, lock, and remove the filter housing from its base. A simple push mechanism actuates the self-driving release and change over means that hold and release the filter housing sump, and provide influent shutoff to prevent leaking and spillage. Rotational shutoff and locking mechanisms are activated and released by axial force on the filter housing at the commencement of the filter changing procedure.
The instant invention is particularly useful as the water filtering system for a refrigerator having water dispensing means and, optionally, an ice dispensing means. The water used in the refrigerator or water and ice may contain contaminants from municipal water sources or from underground well or aquifers. Accordingly, it is advantageous to provide a water filtration system to remove rust, sand, silt, dirt, sediment, heavy metals, microbiological contaminants, such as Giardia cysts, chlorine, pesticides, mercury, benzene, toluene, MTBE, Cadmium bacteria, viruses, and other know contaminants. Particularly useful water filter media for microbiological contaminants include those found in U.S. Pat. Nos. 6,872,311, 6,835,311, 6,797,167, 6,630,016, 6,331,037, and 5,147,722, and are incorporated herein by reference thereto. One of the uses of the instant filter apparatus is as a water filtration apparatus for a refrigerator. Refrigerators are appliances with an outer cabinet, a refrigeration compartment disposed within the outer cabinet and having a rear wall, a pair of opposing side walls, at least one door disposed opposite the rear wall, a top and a bottom and a freezer compartment disposed in the outer cabinet and adjacent to the refrigeration compartment. It is common for refrigerators to have a water dispenser disposed in the door and in fluid communication with a source of water and a filter for filtering the water. Further, it is common for refrigerators to have an ice dispenser in the door and be in fluid communication with a source of water and a filter for filtering the water. It has been found that the filter assembly of the instant invention is useful as a filter for a refrigerator having a water dispenser and/or an ice dispenser.